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Area forecast discussion 
National Weather Service Jackson MS
401 PM CDT Sat Jul 23 2016

Short term...tonight through Sunday night...afternoon shower and
thunderstorm activity has blossomed in the last couple of hours
thanks to daytime heating and the presence of a mesoscale convective vortex located near
Memphis. This has helped send outflow boundaries southward and
generated more convection this afternoon across mainly the central
portion of the County Warning Area. Lapse rates are on the lower side today which
suggests these storms will be a little less potent than we saw
yesterday. Most of this convection will diminish this evening, but
with the shortwave lingering over the region, there will be some
potential for continued shower/storm activity to linger over the area
tonight. How, or if, this convection affects temperatures tonight and
dewpoints will still remain to be seen. Expect that if convection
occurs, it could bring lower overnight lows to some places which
could help limit or slow warming tomorrow. In addition, it could
allow for some low clouds or fog to develop in the morning, again
limiting warming. Despite all of this, still think that locations in
the Delta still have a decent chance of hitting heat advisory
criteria for tomorrow. That being said, we did continue an elevated
heat risk in the severe weather potential statement/graphics but given the uncertainty of overnight
convection, did not extend the current heat advisory at this time.
Will let future shifts assess this continued potential. In addition,
we expanded the limited heat risk for the remainder of the area as
lower rain chances look to exist the further east you go and
persistence suggests these locations should get close to 105 degrees.

Aforementioned shortwave will linger over the region through the
rest of this weekend. This, combined with heat and moisture, will
continue to bring potential for mainly afternoon and evening
convection. /28/

Long term...Monday through next weekend...

Upper ridge that has been entrenched over the region over the past
week will have gradually begun to weaken late this weekend into
Monday. The upper ridge axis will flatten and become more situated
into the Central Plains to eastern rockies. That will help two
decent shortwaves to move through the region. Monday the pw's will
still be pretty high near two inches in the west with some sub 2
inch pw's finally nosing in the east in the wake of the southwest-
westerly moving shortwave moving into the Southern Plains. This
perturbation will continue to move west along the periphery of the
ridge while upper ridging over the western Atlantic will swing in an
easterly wave/TUTT across the Florida Panhandle on Monday morning
into afternoon near the Gulf Coast. This will help keep moisture the
best along the southern half and kept the best probability of precipitation in that area
with less in the north. Heat issues will be less of a concern on
Monday but there will still be lingering high dewpoints in the Delta
and near the I-55 corridor. Highs will be slightly lower in the low-
mid 90s but enough areas topping out in the 103-105 range to include
a limited for heat in the Delta and central Mississippi and north of
I-20 near the I-55 corridor.

A cold front will stall just north of the area early next week and
this in addition to the easterly wave moving over southern Louisiana
and southwest Mississippi will help spark more convection on Tuesday
and into Wednesday, mainly over the southern and western portions of
the region. Heat issues will again be further confined into the
Delta on Tuesday before clouds and convection on Wednesday will help
keep highs into the lower 90s and preclude any heat issues. As the
easterly wave moves northwest out of the area under the ridge
further building west towards The Rockies, a deep trough and cold
front will take shape over the north-Central Plains. Our area will
be in weak ridging but gradually this weakness will increase over
our area, helping to bring the cold front down near our area and
increase rain and storm chances from the north Thursday into the
weekend. This will keep some temperatures down in the north but
overall near normal temperatures and increased chances of storms
later in the work week. /DC/



&&

Aviation...VFR conditions will prevail through much of the taf
period. However, scattered to numerous rain showers/thunderstorms and rain will continue to develop
through the day, primarily during the afternoon and early evening
hours. This activity could bring brief ceiling/visibility reductions
and strong storms will be capable of strong wind gusts. Redevelopment
of areas fog and low stratus resulting in IFR/LIFR flight rules will
be possible late tonight into early Sunday morning, especially in
areas that receive rain today. /Dl/



&&

Preliminary point temps/pops...
Jackson 76 92 74 93 / 40 61 25 35
Meridian 73 94 73 93 / 36 45 23 33
Vicksburg 77 92 75 93 / 39 59 32 35
Hattiesburg 74 92 73 92 / 23 47 25 47
Natchez 76 92 74 92 / 38 60 33 48
Greenville 77 94 75 94 / 43 57 28 40
Greenwood 75 92 75 94 / 42 55 14 34

&&

Jan watches/warnings/advisories...
MS...heat advisory until 7 PM CDT this evening for msz018-019-025-027-
034>057-059>065.

La...heat advisory until 7 PM CDT this evening for laz007>009-015-016-
023>026.

Arkansas...heat advisory until 7 PM CDT this evening for arz074-075.

&&

$$

28/DC/dl

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